1. The first armed drones were created to get Osama bin Laden. In 1998, U.S. President Bill Clinton’s administration shut down an operation to kill the al Qaeda leader in Afghanistan with cruise missiles, given collateral damage estimates of 300 casualties and only 50 percent confidence in the intelligence. As the 9/11 Commission noted, “After this episode Pentagon planners intensified efforts to find a more precise alternative.” In 2000 and 2001, the U.S. Air Force struggled to reconfigure a Hellfire anti-tank missile to fit onto a Predator surveillance drone. Meeting one week before the 9/11 attacks, the National Security Council agreed that the armed Predator was not ready to be operationally deployed. The first known killing by armed drones occurred in November 2001, when a Predator targeted Mohammed Atef, a top al Qaeda military commander, in Afghanistan.

2. So far, drones tend to crash. On Dec. 4, an RQ-170 Sentinel surveillance drone crashed in Iran; a U.S. official involved in the program blamed a lost data link and another unspecific malfunction. Two weeks later, an unarmed Reaper drone crashed at the end of a runway in the Seychelles. “This should not be a surprise,” a defense official toldAviation Week & Space Technology, saying the United States had already lost more than 50 drones. As of July 2010, the Air Force had identified 79 drone accidents costing at least $1 million each. The primary reasons for the crashes: bad weather, loss or disruption of communications links, and “human error factors,” according to the Air Force. As Lt. Gen. David Deptula, former Air Force deputy chief of staff for intelligence, has noted with refreshing honesty, “Some of the [drones] that we have today, you put in a high-threat environment, and they’ll start falling from the sky like rain.”

3. Drones are coming to America. Worried about the militarization of U.S. airspace by unmanned aerial vehicles? As of October, the Federal Aviation Administration (FAA) had reportedly issued 285 active certificates for 85 users, covering 82 drone types. The FAA has refused to say who received the clearances, but it was estimated over a year ago that 35 percent were held by the Pentagon, 11 percent by NASA, and 5 percent by the Department of Homeland Security (DHS). And it’s growing. U.S. Customs and Border Protection already operates eight Predator drones. Under pressure from the congressional Unmanned Systems Caucus — yes, there’s already a drone lobby, with 50 members — two additional Predators were sent to Texas in the fall, though a DHS official noted: “We didn’t ask for them.” Last June, a Predator drone intended to patrol the U.S.-Canada border helped locate three suspected cattle rustlers in North Dakota in what was the first reported use of a drone to arrest U.S. citizens.

4. The scope of U.S. military drone missions is expanding… Drones have come a long way in little more than a decade of military use in strike operations. Five-pound backpack drones are now used by infantry soldiers for tactical surveillance and will soon be deployed for what their manufacturer calls “magic bullet” kamikaze missions. Special operations forces have developed a warhead fired from a Predator drone that can knock down doors. K-Max helicopter drones transport supplies to troops at forward operating bases in Afghanistan. Balloons unleash Tempest drones, which then send out smaller surveillance drones — called Cicadas — that glide to the ground to collect data. And now the U.S. State Department is flying a small fleet of surveillance drones over Iraq to protect the U.S. Embassy there. Bottom line: More and more drones have been rushed into service, and their use and application by the U.S. military is seemingly infinite.

5. …But not as fast as civilian uses. Safety inspectors used drones at Japan’s crippled Fukushima Daiichi nuclear power plant to survey the damage after last year’s tsunami. Archaeologists in Russia are using small drones with infrared cameras to construct a 3-D model of ancient burial mounds. Environmental activists use the Osprey drone to track and monitor Japanese whaling ships. Photographers are developing a celebrity-seeking paparazzi drone. GALE drones will soon fly into hurricanes to more accurately monitor a storm’s strength. And Boeing engineers have joined forces with MIT students to build an iPhone app that can control a drone from up to 3,000 miles away. Last summer, using a laser 3-D printer, University of Southampton engineers built a nearly silent drone that can be assembled by hand in minutes.

6. Most military drones don’t bomb. Although decapitation strikes may get all the headlines, the vast majority of the time, drones are used for intelligence, surveillance, and reconnaissance — what the military calls ISR. The U.S. Navy’s first high-altitude drone can relay black-and-white photos covering roughly half the Persian Gulf; the Global Hawk’s advanced radars make detailed images of the Earth and attempt to sniff out chemical or biological agents for telltale signs of weapons of mass destruction. Soon, the Gorgon Stare drone will “be looking at a whole city, so there will be no way for the adversary to know what we’re looking at, and we can see everything,” according to Maj. Gen. James O. Poss.

7. Attack drones require more boots on the ground. Most unmanned aircraft flown by the U.S. military require not just a ground-based “pilot,” but also a platoon of surveillance analysts (approximately 19 per drone), sensor operators, and a maintenance crew. Some 168 people are required to keep a Predator drone aloft — and 180 for its larger cousin, the Reaper — compared with roughly 100 people for an F-16 fighter jet. To keep up with the demand, the Air Force has trained more drone operators than pilots for the past two years. The upside is that, according to the Congressional Budget Office, drones “are usually less expensive than manned aircraft” ($15 million for a Global Hawk versus about $55 million for a new F-16), though costly sensors and excessive crashes can negate the difference.

8. Drones are becoming a lethal weapon of choice, but nobody’s in charge. Over the past decade, there have been some 300 drone strikes outside the battlefields of Iraq, Afghanistan, and Libya. Of these attacks, 95 percent occurred in Pakistan, with the rest in Yemen and Somalia; cumulatively, they have killed more than 2,000 suspected militants and an unknown number of civilians. Although U.S. President Barack Obama recently acknowledged that “a lot of these strikes” have been in Pakistan’s tribal areas, who can be targeted and under what authority can only be guessed from a few speeches and statements by anonymous U.S. officials. There are believed to be multiple drone-target “kill lists” among government agencies. The 2011 book Top Secret America revealed “three separate ‘kill lists’ of individuals” kept by the National Security Council, the CIA, and the military’s Joint Special Operations Command. In Yemen, the Pentagon is the lead executive authority for some drone strikes (which are reported to the congressional armed services committees), while the CIA is in charge for others (reported to the intelligence committees). As for the Obama administration’s claimed power to assassinate U.S. citizens, such as Yemeni-American cleric Anwar al-Awlaki, the Justice Department refuses to declassify the memo that provided the legal authority to kill him with a drone. So, although 85 percent of non-battlefield drone strikes have occurred under Obama, we have little understanding of their use.

9. Other countries are catching up to the United States. As with most military programs, the United States is far and away the leader in developing drone technology, and the country is projected to account for 77 percent of drone R&D and 69 percent of procurement in the coming decade. Nevertheless, estimates of how many other countries have at least some drone capability now range from 44 to 70, for an estimated 680 drone programs around the world, up greatly from 195 in 2005. China is escalating its drone program, with at least 25 types of systems in development. Iran has also touted its program, including the armed “Ambassador of Death” drone, which President Mahmoud Ahmadinejad unveiled by declaring: “Its main message is peace and friendship.”

10. The drone future is already here. The Pentagon now boasts a fleet of approximately 7,500 drones, up from just 50 a decade ago. According to a congressional report, “manned aircraft have gone from 95% of all [Defense Department] aircraft in 2005 to 69% today.” Over the next decade, the Pentagon expects the number of “multirole” drones — ones that can both spy and strike — to nearly quadruple, to 536. In 2011, the Teal Group consulting firm estimated that worldwide spending on unmanned aerial vehicles will nearly double over the next decade from $5.9 billion to $11.3 billion annually. In the future, drones are projected to: hover just behind infantry soldiers to watch their backs; carry airborne lasers to intercept ballistic missiles; perform aerial refueling; and conduct long-range strategic bombing missions. Given that drones will become cheaper, smaller, faster, stealthier, more lethal, and more autonomous, it is harder to imagine what they won’t do than what they will. Whatever limits drones face will be imposed by us humans — not technology.